Sep 14, 2023

New Marine Protected Area in the Maldives would offer hope for the reef manta ray

Manta Trust researchers photo ID reef mantas in the Maldives. The markings of the creatures are distinctive enough to allow individual identification.

Decked in fins, a mask and snorkel, I’m suspended in the blue, mesmerised and moving just enough to maintain my position, trying to keep my breath steady, as three large shadows emerge from the big beyond, and head my way.

It's early afternoon in Maamunagau Island lagoon, in the Indian Ocean archipelego of the Maldives, when this trio of reef manta rays make their first fly-by. They’re a daunting sight, with broad black ‘wings’ and cavernous mouths, gliding within near-touching distance, before twirling and diving beneath me, as I let out a snorkel-stifled squeal.

After an hour watching their aqua aerobics, apparently oblivious to me and a regular research team from the Manta Trust, these gentle giants seem to have only have one thing on their mind: scooping up as much zooplankton as possible, funnelling the microscopic treats between their distinctive cephalic fins or horns, which have earned them the nickname ‘devilfish’.

Far from devils, Maamunagau's mantas are a delight, as they soar across the reef, dangling above as they cruise Manta Ray Highway. Named after the Spanish word for ‘cloak’ or ‘blanket’, manta rays are known collectively as mobulids, and live between 40 and 50 years in the wild. Classed as ‘megafauna’ due to their super size, reef mantas can measure up to 4.5 metres across and weigh up to 700kg, but are small fry compared to their giant oceanic or pelagic manta ray relations, which are more elusive as they live in the deep ocean. With a wingspan of up to seven metres and weighing up to 2,000kg, oceanic mantas are the world's largest species of ray, with the largest brain-to-body ratio of any cold-blooded species of fish.

The Maldives is famous for its low-lying islands and luxury tourism retreats. The management of protected areas in the archipelago is under evaluation, with a report issued in January aiming to determine the most effective strategy.

Reached by seaplane or boat from the country's main international entry point of Malé, Maamunagau is home to the InterContinental Maldives Maamunagau Resort. With secluded villas fringed by white sand and circled by coral reefs, it's a famously idyllic spot. Now it's also the centre of efforts by British-based The Manta Trust to help protect one of the ocean's most iconic—and imperilled—species.

"Maamunagau Lagoon is an incredibly unique location for manta rays in the Maldives, as it's the first identified manta ray nursery," explains Farah Hamdan, the Raa Atoll Project Manager for the Manta Trust. "For a few months of the year, we see an influx of pregnant mantas coming to this lagoon and preparing to give birth. By February of each year, we start to see several brand-new manta pups zooming around, and because the lagoon is protected from predators and has an abundance of plankton protein for the pups, they will spend a significant amount of time here, only leaving once they’re bigger and more courageous."

Reef mantas are smaller than their deep-water relatives, but can still measure up to 5 metres in length. They are classified as vulnerable by the IUCN Red list.

Large gatherings of mantas were once a common sight across our oceans, but overfishing, pollution, habitat loss and climate change having taken their toll on our precious marine ecosystems and the mantas. With a relatively large number of protected marine areas—relative to the less than 3% of the global ocean free from human pressures—the Maldives remains a hotspot for ocean biodiversity. Home to more than 250 species of corals, more than 1,000 species of fish, and more than 20 whale and dolphin species, the archipelago also hosts the largest aggregation of mantas in the world at Hanifaru Bay in Baa Atoll, a short boat ride from Maamunagau, and a protected Unesco Biosphere Reserve. Hundreds of rays arrive to feed on the plankton in Hanifaru between June and October each year, alongside one of ocean's other megafauna megastars, the whale shark.

In 2005, The Maldivian Manta Ray Project (MMRP) – one of the most comprehensive manta ray conservation studies in the world – was established by Guy Stevens, who completed his PhD on the world's largest population of reef manta rays at the end of 2016. Building on the project's success, Dr. Stevens set up the Manta Trust in 2011, and under his leadership, the UK charity now coordinates more than 25 global manta ray research and conservation projects, including the study that discovered the manta nursery here in the Raa Atoll.

"In 2014, the Manta Trust and its collaborators launched the Global Mobulid Conservation Programme to help protect the world's mantas," says Jess Haines, a Manta Trust project manager who leads trips with the mantas in Raa Atoll, along with two research interns, Tiffany Bond and Anna Knochel.

Critically for an area whose infrastructure is dominated by tourism, the resort is one of those collaborators. "The Manta Trust partnership with InterContinental began in 2019, and involves scientific research, educational programmes with local schools and universities, and essential community projects. Juvenile manta rays are spending lots of their time here due to the movement of plankton, which is dependent on the wind and ocean currents. Wherever the zooplankton goes, the mantas will follow."

Based at the InterContinental's PADI Five-Star Ocean Dive Centre, the project sees the Manta Trust researchers spending hours each day with the mantas in the water, measuring, photographing and identifying the mobulids by their unique spotted markings, and registering their findings with the broader MMRP teams. Many are also given names, and each one we encounter is known personally by the Trust team. During my stay I have close-up wild encounters with Fraenk, Melissa and Kandu Furaana, meaning ‘Ocean Life’ in the local language, Dhivehi.

Each March, the resort is offering a five-night Manta Retreat, giving guests the chance to dive into the mantas’ underwater realm; learning about their complex social behaviour and habits, the plankton they eat, ocean health, coral propagation, and how to ID the mantas from their markings. Crucially, guests also learn about why mantas need protection. While nearby Hanifaru Bay in the Baa Atoll has protective UNESCO status, the Manta Trust is campaigning to secure strong levels of protection for Maamunagau Island's lagoon. Working on legislation with the Maldivian Government, they are hoping the lagoon and its surrounding area will soon be officially designated as a Marine Protected Area (MPA): the first in Raa Atoll.

"Since the lagoon is one of the few locations where scientists are certain that manta pups are born, protecting it is key to ensure the future of manta populations within the region," explains Raa Atoll Project Manager, Farah. Male mantas reach sexual maturity at the relatively late age of 11 and females at 15, giving birth to just one pup every four to five years, so protecting each individual is key in keeping the population stable or helping it to grow. "If we can create a sanctuary for them, the manta adults will come back each year to give birth, and the pups will have a safe space to grow big and strong, before they face the adult world outside the lagoon."

Manta Trust researchers perform a plankton tow to monitor levels of zooplaknton—the reef manta's principal prey. Zooplankton are particularly impacted by water quality and temperature.

The plankton tow deposits samples in a jar attached to a drag net which is then examined for organisms.

That world beyond can be a dangerous place for mantas. Mobulids first appear in fossil record around 28 million years ago, but reef mantas are currently listed as Vulnerable, while oceanic manta rays are classified as Endangered by the International Union for Conservation of Nature (IUCN), moving them one step closer towards extinction. Along with pressures on ocean habitats from plastic pollution and climate change – scientists have predicted a 50% decline in zooplankton biomass as ocean temperatures rise in tropical regions – mantas are also impacted by harmful fishing and trawling practices, with an estimated 13,000 each year caught as bycatch by industrial purse seine fishing vessels targeting tuna.

And just as shark numbers have been decimated in recent decades by the insatiable demand for their fins, manta rays and devil rays have also found themselves in the firing line, targeted for their gill plates: thin cartilage filaments which filter plankton from the water column, known also as pengyusai. Used as Asian dried seafood and in Asian medicine, gill plates are sold as ‘remedies’ for everything from cancer to chicken pox and acne, and are also believed to detoxification of the body, similarly to the way plates filter plankton from the water—despite no scientific evidence to suggest this is true. The Manta Trust's Dr. Guy Stevens also adds, "There is no evidence that manta gill plates were ever a traditional Chinese medicine."

While countries including Indonesia, Peru, The Philippines, Mexico, Australia, Brazil, Malta and the Maldives have laws in place to protect these vulnerable species, others including China, the Philippines, Indonesia, Mozambique, Madagascar, India, Pakistan, Sri Lanka, Brazil, Peru, and Tanzania still trade in gill plates. Harpooned or drowned in nets, manta rays are a soft target for fishermen, with no teeth or venomous spines for defence like sharks and stingrays, and their only option diving or swimming away.

Mobula rays and manta ray gill plates drying on a shore in Sri Lanka. Though mantas are listed as vulnerable, no legal framework exists to prohibit their fishing in countries such as Sri Lanka, where species are fished for the export of their gill plates, used in Asian medicine.

The gill plates are used in medicine said to treat many ailments, from cancer to chickenpox. No scientific evidence exists of any potential benefits.

Due to their increasingly vulnerable status, manta rays were granted legally-binding, international protection under Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in 2013, and this legislation was strengthened for all species of manta rays in 2021. An Appendix-II listing under CITES is designed to ensure that commercial international trade is strictly regulated to ensure its sustainability, legality and traceability for the long-term survival of the species in the wild.

However, as Stevens says, "it is essentially an impossibility for any country to prove that commercial trade in manta body parts is sustainable," and the legislation is often not enforced. In October 2020, one of the largest interceptions of gill plates was made at Hong Kong International Airport: 330kg of plates with an estimated market value of HKD$900,000 (USD $116,000). Labelled as ‘dried fish gills’, the container came from Sri Lanka, where the country's small-scale artisanal fishing fleets are understood to capture more manta and devil rays than the estimated global capture of all industrial purse seine fisheries combined. Conservationists believe extremely unsustainable, proactive fisheries management is urgently needed to protect Sri Lanka's mantas.

A researcher observes a reef manta off Raa Atoll. Combining responsible tourism with research is hoped to be a win-win for local communities, tourists and the animals themselves.

With its Indian Ocean neighbours voraciously chasing short-term gains from fishing—a threat that could lead to the extinction of the slow-breeding species—many of the Maldives’ luxury resorts are aiming to reap the benefits of keeping the archipelago's manta ray populations healthy and alive. Along with diving, dolphin sunset tours, and swimming with turtles and whale sharks, snorkelling with wild manta rays has become one of the world's most coveted bucket-list wildlife experiences, generating millions of tourist dollars each year—whichm if responsible, can be invested into conservation with benefits extending to local communities.

"Abolishing harmful fishing practices, bringing in tougher penalties for illegal fishing, improving ocean habitats and protecting the manta rays’ feeding, breeding and nursery sites is essential if we are going to see these incredible animals survive and thrive," says the Manta Trust's Jess, as we head out on the dive boat into Maamunagau's lagoon. "We’re working very hard to ensure we create a safe and secure environment for the mantas. We owe it to them to ensure the species is around for many, many years to come."

Lauren Jarvis is a freelance journalist based in London. Follow her on Instagram.